A196836 - OEIS

A196836

a(n) = (1^n + 2^n +3^n + 4^n)/2.

2, 5, 15, 50, 177, 650, 2445, 9350, 36177, 141170, 554325, 2186750, 8656377, 34355690, 136617405, 544061750, 2169039777, 8654570210, 34553579685, 138020346350, 551499730377, 2204254480730, 8811785649165, 35231447872550, 140878711512177, 563373614503250

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OFFSET

0,1

COMMENTS

2*a(n) = A001551(n), n>=0.

LINKS

Table of n, a(n) for n=0..25.

FORMULA

a(n) = (1^n + 2^n + 3^n + 4^n)/2, n>=0.

E.g.f.: (1-exp(4*x))/(2*(exp(-x)-1)) = Sum_{j=1..4} exp(j*x)/2.

O.g.f.: (2-5*x)*(1-5*x+5*x^2)/(Product_{j=1..4} (1-j*x)) (via Laplace transformation of the o.g.f.).

MATHEMATICA